Non-Intrusive Live Fiber Detection
Detect active signals while the fiber remains in service, avoiding unnecessary disconnects during identification and maintenance.
The FID-30R / FID-31R identifies optical activity by gently bending the coated fiber inside the clamp head and detecting leaked light. This allows technicians to check for Tone, Traffic and ONU signals without disconnecting the fiber from service.
For live networks, that helps reduce the risk of working on the wrong fiber and gives the technician an immediate indication of optical activity and signal direction before proceeding with maintenance.
Optical fiber identifier with built-in optical power meter.
Optical fiber identifier without built-in optical power meter.
Detect active signals while the fiber remains in service, avoiding unnecessary disconnects during identification and maintenance.
One clamp head covers 250 µm single fiber, up to 3 mm jacketed cord and up to 12-fiber ribbon.
Select Normal, Fast or Fine measurement mode according to the required sensitivity and the condition of the link.
The instrument can alert the user when strong external light may cause a false Traffic-signal indication.
| Function | FID-30R | FID-31R |
|---|---|---|
| Optical Fiber Identification | Yes | Yes |
| ONU Detection | Yes | Yes |
| Built-In Optical Power Meter | Yes | No |
| Approx. Weight incl. Battery | 235 g | 220 g |
The supplied datasheet describes detection of Tone, Traffic and ONU signals. The measurement mode can be switched between Normal, Fast and Fine according to the application and line conditions.

| Parameter | Published Specification |
|---|---|
| Applicable Fiber | Single-mode optical fiber / multimode optical fiber; approx. 125 µm cladding |
| Applicable Cable | 250–900 µm coated fiber; up to 12-fiber ribbon; 1100–3000 µm jacketed cord |
| Wavelength Range | 850–1650 nm |
| Display Range – Fast Mode | 23 to -62 dBm |
| Display Range – Normal Mode | 23 to -67 dBm |
| Display Range – Fine Mode | 23 to -73 dBm |
| Detectable Tone Frequencies | 270 Hz, 330 Hz, 1 kHz, 2 kHz |
| Live Fiber Detection Display Range | 23 to -59 dBm |
| Dimensions | Approx. W50 × D210 × H113 mm, without projection |
| Weight | FID-31R approx. 220 g incl. battery; FID-30R approx. 235 g incl. battery |
| Operating Temperature | -10°C to +50°C |
| Storage Temperature | -20°C to +60°C |
| Humidity | 0 to 95% RH non-condensing in operation/storage |
| Interface | USB 2.0 Mini-B for firmware update |
| Power Source | 2 × LR6 / AA dry batteries |
| Battery Life | Approx. 8 hours under the source-defined test condition |
| Display | 2.4-inch TFT LCD with touch screen |
| Trigger | Trigger hold function |

The FID-30R includes an integrated optical power meter. The source lists Traffic-signal measurement at 1310 / 1490 / 1550 nm and Tone-signal measurement at 270 Hz / 330 Hz / 1 kHz / 2 kHz.
| Power Meter Parameter | FID-30R |
|---|---|
| Wavelengths | 1310 nm, 1490 nm, 1550 nm |
| Measurement Range – Modulated Tone | 10 to -60 dBm |
| Measurement Range – CW / Traffic | 10 to -40 dBm |
| Accuracy | ±0.3 dB under the source-defined condition |
| Optical Connector Heads | Selectable optional heads for FC, UC, LC and SC connector types |

Both FID-30R and FID-31R support ONU detection. The source lists detection for common upstream/downstream PON wavelengths and explicitly notes that not every ONU is guaranteed to be detected.
Engineering note: preserve Fujikura’s qualification that some ONU waveforms may not be detected without analysis/optimization. Do not turn ONU support into a universal-detection claim.
Confirm whether a fiber is active before splicing, cutting, rerouting or maintenance work.
Identify Traffic and ONU activity in access-network infrastructure without disconnecting the optical path.
Use signal direction and Tone detection to identify the intended fiber in dense cable environments.
The source positions the FID-30R/FID-31R as optical fiber identifiers for fiber-optic data communications cables.
| Standard Package Item | Model | Qty |
|---|---|---|
| Optical Fiber Identifier | FID-30R / FID-31R | 1 pc |
| Soft Case | FID-CASE-02 | 1 pc |
| Instruction Manual | M-FID30R | 1 pc |
| Quick Reference Guide | QRG-07-E or J | 1 pc |
| Strap | ST-01 | 1 pc |
| Option | Model | Remark |
|---|---|---|
| Optical Connector Head | OCH-02-FC | FC type |
| Optical Connector Head | OCH-02-UC | UC type |
| Optical Connector Head | OCH-02-LC | LC type |
| Optical Connector Head | OCH-02-SC | SC type |
| USB Cable | USB-01 | USB(A) – USB(mini-B) |
